Merge branch 'turbovnc'

Conflicts, resolved manually:
	AUTHORS
pull/1/head
Christian Beier 11 years ago
commit 413ca0dfef

@ -35,7 +35,7 @@ Noriaki Yamazaki, Ben Klopfenstein, Vic Lee, Christian Beier,
Alexander Dorokhine, Corentin Chary, Wouter Van Meir, George Kiagiadakis,
Joel Martin, Gernot Tenchio, William Roberts, Cristian Rodríguez,
George Fleury, Kan-Ru Chen, Steve Guo, Luca Stauble, Peter Watkins,
Kyle J. McKay, Mateus Cesar Groess and Philip Van Hoof.
Kyle J. McKay, Mateus Cesar Groess, Philip Van Hoof and D. R. Commander.
Probably I forgot quite a few people sending a patch here and there, which
really made a difference. Without those, some obscure bugs still would

@ -5,6 +5,9 @@ include(CheckFunctionExists)
include(CheckIncludeFile)
include(CheckTypeSize)
include(TestBigEndian)
include(CheckCSourceCompiles)
include(CheckCXXSourceCompiles)
include(CheckCSourceRuns)
set(PACKAGE_NAME "LibVNCServer")
set(FULL_PACKAGE_NAME "LibVNCServer")
@ -30,6 +33,40 @@ find_package(X11)
find_package(OpenSSL)
find_library(LIBGCRYPT_LIBRARIES gcrypt)
# Check whether the version of libjpeg we found was libjpeg-turbo and print a
# warning if not.
set(CMAKE_REQUIRED_LIBRARIES ${JPEG_LIBRARIES})
set(CMAKE_REQUIRED_FLAGS -I${JPEG_INCLUDE_DIR})
set(JPEG_TEST_SOURCE "\n
#include <stdio.h>\n
#include <jpeglib.h>\n
int main(void) {\n
struct jpeg_compress_struct cinfo;\n
struct jpeg_error_mgr jerr;\n
cinfo.err=jpeg_std_error(&jerr);\n
jpeg_create_compress(&cinfo);\n
cinfo.input_components = 3;\n
jpeg_set_defaults(&cinfo);\n
cinfo.in_color_space = JCS_EXT_RGB;\n
jpeg_default_colorspace(&cinfo);\n
return 0;\n
}")
if(CMAKE_CROSSCOMPILING)
check_c_source_compiles("${JPEG_TEST_SOURCE}" FOUND_LIBJPEG_TURBO)
else()
check_c_source_runs("${JPEG_TEST_SOURCE}" FOUND_LIBJPEG_TURBO)
endif()
set(CMAKE_REQUIRED_LIBRARIES)
set(CMAKE_REQUIRED_FLAGS)
set(CMAKE_REQUIRED_DEFINITIONS)
if(NOT FOUND_LIBJPEG_TURBO)
message(WARNING "*** The libjpeg library you are building against is not libjpeg-turbo. Performance will be reduced. You can obtain libjpeg-turbo from: https://sourceforge.net/projects/libjpeg-turbo/files/ ***")
endif()
set(CMAKE_REQUIRED_LIBRARIES resolv)
check_function_exists(__b64_ntop HAVE_B64)
@ -166,13 +203,13 @@ endif(ZLIB_FOUND)
if(JPEG_FOUND)
add_definitions(-DLIBVNCSERVER_HAVE_LIBJPEG)
include_directories(${JPEG_INCLUDE_DIR})
set(TIGHT_C ${LIBVNCSERVER_DIR}/tight.c)
set(TIGHT_C ${LIBVNCSERVER_DIR}/tight.c ${COMMON_DIR}/turbojpeg.c)
endif(JPEG_FOUND)
if(PNG_FOUND)
add_definitions(-DLIBVNCSERVER_HAVE_LIBPNG)
include_directories(${PNG_INCLUDE_DIR})
set(TIGHT_C ${LIBVNCSERVER_DIR}/tight.c)
set(TIGHT_C ${LIBVNCSERVER_DIR}/tight.c ${COMMON_DIR}/turbojpeg.c)
endif(PNG_FOUND)
set(LIBVNCSERVER_SOURCES

@ -0,0 +1,849 @@
/*
* Copyright (C)2009-2012 D. R. Commander. All Rights Reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions are met:
*
* - Redistributions of source code must retain the above copyright notice,
* this list of conditions and the following disclaimer.
* - Redistributions in binary form must reproduce the above copyright notice,
* this list of conditions and the following disclaimer in the documentation
* and/or other materials provided with the distribution.
* - Neither the name of the libjpeg-turbo Project nor the names of its
* contributors may be used to endorse or promote products derived from this
* software without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS",
* AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDERS OR CONTRIBUTORS BE
* LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
* CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
* SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
* INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
* CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
* ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
* POSSIBILITY OF SUCH DAMAGE.
*/
/* TurboJPEG/OSS: this implements the TurboJPEG API using libjpeg-turbo */
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#ifndef JCS_EXTENSIONS
#define JPEG_INTERNAL_OPTIONS
#endif
#include <jpeglib.h>
#include <jerror.h>
#include <setjmp.h>
#include "./turbojpeg.h"
#define PAD(v, p) ((v+(p)-1)&(~((p)-1)))
#define CSTATE_START 100
#define DSTATE_START 200
#define MEMZERO(ptr, size) memset(ptr, 0, size)
#ifndef min
#define min(a,b) ((a)<(b)?(a):(b))
#endif
#ifndef max
#define max(a,b) ((a)>(b)?(a):(b))
#endif
/* Error handling (based on example in example.c) */
static char errStr[JMSG_LENGTH_MAX]="No error";
struct my_error_mgr
{
struct jpeg_error_mgr pub;
jmp_buf setjmp_buffer;
};
typedef struct my_error_mgr *my_error_ptr;
static void my_error_exit(j_common_ptr cinfo)
{
my_error_ptr myerr=(my_error_ptr)cinfo->err;
(*cinfo->err->output_message)(cinfo);
longjmp(myerr->setjmp_buffer, 1);
}
/* Based on output_message() in jerror.c */
static void my_output_message(j_common_ptr cinfo)
{
(*cinfo->err->format_message)(cinfo, errStr);
}
/* Global structures, macros, etc. */
enum {COMPRESS=1, DECOMPRESS=2};
typedef struct _tjinstance
{
struct jpeg_compress_struct cinfo;
struct jpeg_decompress_struct dinfo;
struct jpeg_destination_mgr jdst;
struct jpeg_source_mgr jsrc;
struct my_error_mgr jerr;
int init;
} tjinstance;
static const int pixelsize[TJ_NUMSAMP]={3, 3, 3, 1, 3};
#define NUMSF 4
static const tjscalingfactor sf[NUMSF]={
{1, 1},
{1, 2},
{1, 4},
{1, 8}
};
#define _throw(m) {snprintf(errStr, JMSG_LENGTH_MAX, "%s", m); \
retval=-1; goto bailout;}
#define getinstance(handle) tjinstance *this=(tjinstance *)handle; \
j_compress_ptr cinfo=NULL; j_decompress_ptr dinfo=NULL; \
if(!this) {snprintf(errStr, JMSG_LENGTH_MAX, "Invalid handle"); \
return -1;} \
cinfo=&this->cinfo; dinfo=&this->dinfo;
static int getPixelFormat(int pixelSize, int flags)
{
if(pixelSize==1) return TJPF_GRAY;
if(pixelSize==3)
{
if(flags&TJ_BGR) return TJPF_BGR;
else return TJPF_RGB;
}
if(pixelSize==4)
{
if(flags&TJ_ALPHAFIRST)
{
if(flags&TJ_BGR) return TJPF_XBGR;
else return TJPF_XRGB;
}
else
{
if(flags&TJ_BGR) return TJPF_BGRX;
else return TJPF_RGBX;
}
}
return -1;
}
static int setCompDefaults(struct jpeg_compress_struct *cinfo,
int pixelFormat, int subsamp, int jpegQual)
{
int retval=0;
switch(pixelFormat)
{
case TJPF_GRAY:
cinfo->in_color_space=JCS_GRAYSCALE; break;
#if JCS_EXTENSIONS==1
case TJPF_RGB:
cinfo->in_color_space=JCS_EXT_RGB; break;
case TJPF_BGR:
cinfo->in_color_space=JCS_EXT_BGR; break;
case TJPF_RGBX:
case TJPF_RGBA:
cinfo->in_color_space=JCS_EXT_RGBX; break;
case TJPF_BGRX:
case TJPF_BGRA:
cinfo->in_color_space=JCS_EXT_BGRX; break;
case TJPF_XRGB:
case TJPF_ARGB:
cinfo->in_color_space=JCS_EXT_XRGB; break;
case TJPF_XBGR:
case TJPF_ABGR:
cinfo->in_color_space=JCS_EXT_XBGR; break;
#else
case TJPF_RGB:
case TJPF_BGR:
case TJPF_RGBX:
case TJPF_BGRX:
case TJPF_XRGB:
case TJPF_XBGR:
case TJPF_RGBA:
case TJPF_BGRA:
case TJPF_ARGB:
case TJPF_ABGR:
cinfo->in_color_space=JCS_RGB; pixelFormat=TJPF_RGB;
break;
#endif
}
cinfo->input_components=tjPixelSize[pixelFormat];
jpeg_set_defaults(cinfo);
if(jpegQual>=0)
{
jpeg_set_quality(cinfo, jpegQual, TRUE);
if(jpegQual>=96) cinfo->dct_method=JDCT_ISLOW;
else cinfo->dct_method=JDCT_FASTEST;
}
if(subsamp==TJSAMP_GRAY)
jpeg_set_colorspace(cinfo, JCS_GRAYSCALE);
else
jpeg_set_colorspace(cinfo, JCS_YCbCr);
cinfo->comp_info[0].h_samp_factor=tjMCUWidth[subsamp]/8;
cinfo->comp_info[1].h_samp_factor=1;
cinfo->comp_info[2].h_samp_factor=1;
cinfo->comp_info[0].v_samp_factor=tjMCUHeight[subsamp]/8;
cinfo->comp_info[1].v_samp_factor=1;
cinfo->comp_info[2].v_samp_factor=1;
return retval;
}
static int setDecompDefaults(struct jpeg_decompress_struct *dinfo,
int pixelFormat)
{
int retval=0;
switch(pixelFormat)
{
case TJPF_GRAY:
dinfo->out_color_space=JCS_GRAYSCALE; break;
#if JCS_EXTENSIONS==1
case TJPF_RGB:
dinfo->out_color_space=JCS_EXT_RGB; break;
case TJPF_BGR:
dinfo->out_color_space=JCS_EXT_BGR; break;
case TJPF_RGBX:
dinfo->out_color_space=JCS_EXT_RGBX; break;
case TJPF_BGRX:
dinfo->out_color_space=JCS_EXT_BGRX; break;
case TJPF_XRGB:
dinfo->out_color_space=JCS_EXT_XRGB; break;
case TJPF_XBGR:
dinfo->out_color_space=JCS_EXT_XBGR; break;
#if JCS_ALPHA_EXTENSIONS==1
case TJPF_RGBA:
dinfo->out_color_space=JCS_EXT_RGBA; break;
case TJPF_BGRA:
dinfo->out_color_space=JCS_EXT_BGRA; break;
case TJPF_ARGB:
dinfo->out_color_space=JCS_EXT_ARGB; break;
case TJPF_ABGR:
dinfo->out_color_space=JCS_EXT_ABGR; break;
#endif
#else
case TJPF_RGB:
case TJPF_BGR:
case TJPF_RGBX:
case TJPF_BGRX:
case TJPF_XRGB:
case TJPF_XBGR:
case TJPF_RGBA:
case TJPF_BGRA:
case TJPF_ARGB:
case TJPF_ABGR:
dinfo->out_color_space=JCS_RGB; break;
#endif
default:
_throw("Unsupported pixel format");
}
bailout:
return retval;
}
static int getSubsamp(j_decompress_ptr dinfo)
{
int retval=-1, i, k;
for(i=0; i<NUMSUBOPT; i++)
{
if(dinfo->num_components==pixelsize[i])
{
if(dinfo->comp_info[0].h_samp_factor==tjMCUWidth[i]/8
&& dinfo->comp_info[0].v_samp_factor==tjMCUHeight[i]/8)
{
int match=0;
for(k=1; k<dinfo->num_components; k++)
{
if(dinfo->comp_info[k].h_samp_factor==1
&& dinfo->comp_info[k].v_samp_factor==1)
match++;
}
if(match==dinfo->num_components-1)
{
retval=i; break;
}
}
}
}
return retval;
}
#ifndef JCS_EXTENSIONS
/* Conversion functions to emulate the colorspace extensions. This allows the
TurboJPEG wrapper to be used with libjpeg */
#define TORGB(PS, ROFFSET, GOFFSET, BOFFSET) { \
int rowPad=pitch-width*PS; \
while(height--) \
{ \
unsigned char *endOfRow=src+width*PS; \
while(src<endOfRow) \
{ \
dst[RGB_RED]=src[ROFFSET]; \
dst[RGB_GREEN]=src[GOFFSET]; \
dst[RGB_BLUE]=src[BOFFSET]; \
dst+=RGB_PIXELSIZE; src+=PS; \
} \
src+=rowPad; \
} \
}
static unsigned char *toRGB(unsigned char *src, int width, int pitch,
int height, int pixelFormat, unsigned char *dst)
{
unsigned char *retval=src;
switch(pixelFormat)
{
case TJPF_RGB:
#if RGB_RED!=0 || RGB_GREEN!=1 || RGB_BLUE!=2 || RGB_PIXELSIZE!=3
retval=dst; TORGB(3, 0, 1, 2);
#endif
break;
case TJPF_BGR:
#if RGB_RED!=2 || RGB_GREEN!=1 || RGB_BLUE!=0 || RGB_PIXELSIZE!=3
retval=dst; TORGB(3, 2, 1, 0);
#endif
break;
case TJPF_RGBX:
case TJPF_RGBA:
#if RGB_RED!=0 || RGB_GREEN!=1 || RGB_BLUE!=2 || RGB_PIXELSIZE!=4
retval=dst; TORGB(4, 0, 1, 2);
#endif
break;
case TJPF_BGRX:
case TJPF_BGRA:
#if RGB_RED!=2 || RGB_GREEN!=1 || RGB_BLUE!=0 || RGB_PIXELSIZE!=4
retval=dst; TORGB(4, 2, 1, 0);
#endif
break;
case TJPF_XRGB:
case TJPF_ARGB:
#if RGB_RED!=1 || RGB_GREEN!=2 || RGB_BLUE!=3 || RGB_PIXELSIZE!=4
retval=dst; TORGB(4, 1, 2, 3);
#endif
break;
case TJPF_XBGR:
case TJPF_ABGR:
#if RGB_RED!=3 || RGB_GREEN!=2 || RGB_BLUE!=1 || RGB_PIXELSIZE!=4
retval=dst; TORGB(4, 3, 2, 1);
#endif
break;
}
return retval;
}
#define FROMRGB(PS, ROFFSET, GOFFSET, BOFFSET, SETALPHA) { \
int rowPad=pitch-width*PS; \
while(height--) \
{ \
unsigned char *endOfRow=dst+width*PS; \
while(dst<endOfRow) \
{ \
dst[ROFFSET]=src[RGB_RED]; \
dst[GOFFSET]=src[RGB_GREEN]; \
dst[BOFFSET]=src[RGB_BLUE]; \
SETALPHA \
dst+=PS; src+=RGB_PIXELSIZE; \
} \
dst+=rowPad; \
} \
}
static void fromRGB(unsigned char *src, unsigned char *dst, int width,
int pitch, int height, int pixelFormat)
{
switch(pixelFormat)
{
case TJPF_RGB:
#if RGB_RED!=0 || RGB_GREEN!=1 || RGB_BLUE!=2 || RGB_PIXELSIZE!=3
FROMRGB(3, 0, 1, 2,);
#endif
break;
case TJPF_BGR:
#if RGB_RED!=2 || RGB_GREEN!=1 || RGB_BLUE!=0 || RGB_PIXELSIZE!=3
FROMRGB(3, 2, 1, 0,);
#endif
break;
case TJPF_RGBX:
#if RGB_RED!=0 || RGB_GREEN!=1 || RGB_BLUE!=2 || RGB_PIXELSIZE!=4
FROMRGB(4, 0, 1, 2,);
#endif
break;
case TJPF_RGBA:
#if RGB_RED!=0 || RGB_GREEN!=1 || RGB_BLUE!=2 || RGB_PIXELSIZE!=4
FROMRGB(4, 0, 1, 2, dst[3]=0xFF;);
#endif
break;
case TJPF_BGRX:
#if RGB_RED!=2 || RGB_GREEN!=1 || RGB_BLUE!=0 || RGB_PIXELSIZE!=4
FROMRGB(4, 2, 1, 0,);
#endif
break;
case TJPF_BGRA:
#if RGB_RED!=2 || RGB_GREEN!=1 || RGB_BLUE!=0 || RGB_PIXELSIZE!=4
FROMRGB(4, 2, 1, 0, dst[3]=0xFF;); return;
#endif
break;
case TJPF_XRGB:
#if RGB_RED!=1 || RGB_GREEN!=2 || RGB_BLUE!=3 || RGB_PIXELSIZE!=4
FROMRGB(4, 1, 2, 3,); return;
#endif
break;
case TJPF_ARGB:
#if RGB_RED!=1 || RGB_GREEN!=2 || RGB_BLUE!=3 || RGB_PIXELSIZE!=4
FROMRGB(4, 1, 2, 3, dst[0]=0xFF;); return;
#endif
break;
case TJPF_XBGR:
#if RGB_RED!=3 || RGB_GREEN!=2 || RGB_BLUE!=1 || RGB_PIXELSIZE!=4
FROMRGB(4, 3, 2, 1,); return;
#endif
break;
case TJPF_ABGR:
#if RGB_RED!=3 || RGB_GREEN!=2 || RGB_BLUE!=1 || RGB_PIXELSIZE!=4
FROMRGB(4, 3, 2, 1, dst[0]=0xFF;); return;
#endif
break;
}
}
#endif
/* General API functions */
DLLEXPORT char* DLLCALL tjGetErrorStr(void)
{
return errStr;
}
DLLEXPORT int DLLCALL tjDestroy(tjhandle handle)
{
getinstance(handle);
if(setjmp(this->jerr.setjmp_buffer)) return -1;
if(this->init&COMPRESS) jpeg_destroy_compress(cinfo);
if(this->init&DECOMPRESS) jpeg_destroy_decompress(dinfo);
free(this);
return 0;
}
/* Compressor */
static boolean empty_output_buffer(j_compress_ptr cinfo)
{
ERREXIT(cinfo, JERR_BUFFER_SIZE);
return TRUE;
}
static void dst_noop(j_compress_ptr cinfo)
{
}
static tjhandle _tjInitCompress(tjinstance *this)
{
/* This is also straight out of example.c */
this->cinfo.err=jpeg_std_error(&this->jerr.pub);
this->jerr.pub.error_exit=my_error_exit;
this->jerr.pub.output_message=my_output_message;
if(setjmp(this->jerr.setjmp_buffer))
{
/* If we get here, the JPEG code has signaled an error. */
if(this) free(this); return NULL;
}
jpeg_create_compress(&this->cinfo);
this->cinfo.dest=&this->jdst;
this->jdst.init_destination=dst_noop;
this->jdst.empty_output_buffer=empty_output_buffer;
this->jdst.term_destination=dst_noop;
this->init|=COMPRESS;
return (tjhandle)this;
}
DLLEXPORT tjhandle DLLCALL tjInitCompress(void)
{
tjinstance *this=NULL;
if((this=(tjinstance *)malloc(sizeof(tjinstance)))==NULL)
{
snprintf(errStr, JMSG_LENGTH_MAX,
"tjInitCompress(): Memory allocation failure");
return NULL;
}
MEMZERO(this, sizeof(tjinstance));
return _tjInitCompress(this);
}
DLLEXPORT unsigned long DLLCALL tjBufSize(int width, int height,
int jpegSubsamp)
{
unsigned long retval=0; int mcuw, mcuh, chromasf;
if(width<1 || height<1 || jpegSubsamp<0 || jpegSubsamp>=NUMSUBOPT)
_throw("tjBufSize(): Invalid argument");
// This allows for rare corner cases in which a JPEG image can actually be
// larger than the uncompressed input (we wouldn't mention it if it hadn't
// happened before.)
mcuw=tjMCUWidth[jpegSubsamp];
mcuh=tjMCUHeight[jpegSubsamp];
chromasf=jpegSubsamp==TJSAMP_GRAY? 0: 4*64/(mcuw*mcuh);
retval=PAD(width, mcuw) * PAD(height, mcuh) * (2 + chromasf) + 2048;
bailout:
return retval;
}
DLLEXPORT unsigned long DLLCALL TJBUFSIZE(int width, int height)
{
unsigned long retval=0;
if(width<1 || height<1)
_throw("TJBUFSIZE(): Invalid argument");
// This allows for rare corner cases in which a JPEG image can actually be
// larger than the uncompressed input (we wouldn't mention it if it hadn't
// happened before.)
retval=PAD(width, 16) * PAD(height, 16) * 6 + 2048;
bailout:
return retval;
}
DLLEXPORT int DLLCALL tjCompress2(tjhandle handle, unsigned char *srcBuf,
int width, int pitch, int height, int pixelFormat, unsigned char **jpegBuf,
unsigned long *jpegSize, int jpegSubsamp, int jpegQual, int flags)
{
int i, retval=0; JSAMPROW *row_pointer=NULL;
#ifndef JCS_EXTENSIONS
unsigned char *rgbBuf=NULL;
#endif
getinstance(handle)
if((this->init&COMPRESS)==0)
_throw("tjCompress2(): Instance has not been initialized for compression");
if(srcBuf==NULL || width<=0 || pitch<0 || height<=0 || pixelFormat<0
|| pixelFormat>=TJ_NUMPF || jpegBuf==NULL || jpegSize==NULL
|| jpegSubsamp<0 || jpegSubsamp>=NUMSUBOPT || jpegQual<0 || jpegQual>100)
_throw("tjCompress2(): Invalid argument");
if(setjmp(this->jerr.setjmp_buffer))
{
/* If we get here, the JPEG code has signaled an error. */
retval=-1;
goto bailout;
}
if(pitch==0) pitch=width*tjPixelSize[pixelFormat];
#ifndef JCS_EXTENSIONS
if(pixelFormat!=TJPF_GRAY)
{
rgbBuf=(unsigned char *)malloc(width*height*RGB_PIXELSIZE);
if(!rgbBuf) _throw("tjCompress2(): Memory allocation failure");
srcBuf=toRGB(srcBuf, width, pitch, height, pixelFormat, rgbBuf);
pitch=width*RGB_PIXELSIZE;
}
#endif
cinfo->image_width=width;
cinfo->image_height=height;
if(flags&TJFLAG_FORCEMMX) putenv("JSIMD_FORCEMMX=1");
else if(flags&TJFLAG_FORCESSE) putenv("JSIMD_FORCESSE=1");
else if(flags&TJFLAG_FORCESSE2) putenv("JSIMD_FORCESSE2=1");
if(setCompDefaults(cinfo, pixelFormat, jpegSubsamp, jpegQual)==-1)
return -1;
this->jdst.next_output_byte=*jpegBuf;
this->jdst.free_in_buffer=tjBufSize(width, height, jpegSubsamp);
jpeg_start_compress(cinfo, TRUE);
if((row_pointer=(JSAMPROW *)malloc(sizeof(JSAMPROW)*height))==NULL)
_throw("tjCompress2(): Memory allocation failure");
for(i=0; i<height; i++)
{
if(flags&TJFLAG_BOTTOMUP) row_pointer[i]=&srcBuf[(height-i-1)*pitch];
else row_pointer[i]=&srcBuf[i*pitch];
}
while(cinfo->next_scanline<cinfo->image_height)
{
jpeg_write_scanlines(cinfo, &row_pointer[cinfo->next_scanline],
cinfo->image_height-cinfo->next_scanline);
}
jpeg_finish_compress(cinfo);
*jpegSize=tjBufSize(width, height, jpegSubsamp)
-(unsigned long)(this->jdst.free_in_buffer);
bailout:
if(cinfo->global_state>CSTATE_START) jpeg_abort_compress(cinfo);
#ifndef JCS_EXTENSIONS
if(rgbBuf) free(rgbBuf);
#endif
if(row_pointer) free(row_pointer);
return retval;
}
DLLEXPORT int DLLCALL tjCompress(tjhandle handle, unsigned char *srcBuf,
int width, int pitch, int height, int pixelSize, unsigned char *jpegBuf,
unsigned long *jpegSize, int jpegSubsamp, int jpegQual, int flags)
{
int retval=0; unsigned long size;
retval=tjCompress2(handle, srcBuf, width, pitch, height,
getPixelFormat(pixelSize, flags), &jpegBuf, &size, jpegSubsamp, jpegQual,
flags);
*jpegSize=size;
return retval;
}
/* Decompressor */
static boolean fill_input_buffer(j_decompress_ptr dinfo)
{
ERREXIT(dinfo, JERR_BUFFER_SIZE);
return TRUE;
}
static void skip_input_data(j_decompress_ptr dinfo, long num_bytes)
{
dinfo->src->next_input_byte += (size_t) num_bytes;
dinfo->src->bytes_in_buffer -= (size_t) num_bytes;
}
static void src_noop(j_decompress_ptr dinfo)
{
}
static tjhandle _tjInitDecompress(tjinstance *this)
{
/* This is also straight out of example.c */
this->dinfo.err=jpeg_std_error(&this->jerr.pub);
this->jerr.pub.error_exit=my_error_exit;
this->jerr.pub.output_message=my_output_message;
if(setjmp(this->jerr.setjmp_buffer))
{
/* If we get here, the JPEG code has signaled an error. */
if(this) free(this); return NULL;
}
jpeg_create_decompress(&this->dinfo);
this->dinfo.src=&this->jsrc;
this->jsrc.init_source=src_noop;
this->jsrc.fill_input_buffer=fill_input_buffer;
this->jsrc.skip_input_data=skip_input_data;
this->jsrc.resync_to_restart=jpeg_resync_to_restart;
this->jsrc.term_source=src_noop;
this->init|=DECOMPRESS;
return (tjhandle)this;
}
DLLEXPORT tjhandle DLLCALL tjInitDecompress(void)
{
tjinstance *this;
if((this=(tjinstance *)malloc(sizeof(tjinstance)))==NULL)
{
snprintf(errStr, JMSG_LENGTH_MAX,
"tjInitDecompress(): Memory allocation failure");
return NULL;
}
MEMZERO(this, sizeof(tjinstance));
return _tjInitDecompress(this);
}
DLLEXPORT int DLLCALL tjDecompressHeader2(tjhandle handle,
unsigned char *jpegBuf, unsigned long jpegSize, int *width, int *height,
int *jpegSubsamp)
{
int retval=0;
getinstance(handle);
if((this->init&DECOMPRESS)==0)
_throw("tjDecompressHeader2(): Instance has not been initialized for decompression");
if(jpegBuf==NULL || jpegSize<=0 || width==NULL || height==NULL
|| jpegSubsamp==NULL)
_throw("tjDecompressHeader2(): Invalid argument");
if(setjmp(this->jerr.setjmp_buffer))
{
/* If we get here, the JPEG code has signaled an error. */
return -1;
}
this->jsrc.bytes_in_buffer=jpegSize;
this->jsrc.next_input_byte=jpegBuf;
jpeg_read_header(dinfo, TRUE);
*width=dinfo->image_width;
*height=dinfo->image_height;
*jpegSubsamp=getSubsamp(dinfo);
jpeg_abort_decompress(dinfo);
if(*jpegSubsamp<0)
_throw("tjDecompressHeader2(): Could not determine subsampling type for JPEG image");
if(*width<1 || *height<1)
_throw("tjDecompressHeader2(): Invalid data returned in header");
bailout:
return retval;
}
DLLEXPORT int DLLCALL tjDecompressHeader(tjhandle handle,
unsigned char *jpegBuf, unsigned long jpegSize, int *width, int *height)
{
int jpegSubsamp;
return tjDecompressHeader2(handle, jpegBuf, jpegSize, width, height,
&jpegSubsamp);
}
DLLEXPORT tjscalingfactor* DLLCALL tjGetScalingFactors(int *numscalingfactors)
{
if(numscalingfactors==NULL)
{
snprintf(errStr, JMSG_LENGTH_MAX,
"tjGetScalingFactors(): Invalid argument");
return NULL;
}
*numscalingfactors=NUMSF;
return (tjscalingfactor *)sf;
}
DLLEXPORT int DLLCALL tjDecompress2(tjhandle handle, unsigned char *jpegBuf,
unsigned long jpegSize, unsigned char *dstBuf, int width, int pitch,
int height, int pixelFormat, int flags)
{
int i, retval=0; JSAMPROW *row_pointer=NULL;
int jpegwidth, jpegheight, scaledw, scaledh;
#ifndef JCS_EXTENSIONS
unsigned char *rgbBuf=NULL;
unsigned char *_dstBuf=NULL; int _pitch=0;
#endif
getinstance(handle);
if((this->init&DECOMPRESS)==0)
_throw("tjDecompress2(): Instance has not been initialized for decompression");
if(jpegBuf==NULL || jpegSize<=0 || dstBuf==NULL || width<0 || pitch<0
|| height<0 || pixelFormat<0 || pixelFormat>=TJ_NUMPF)
_throw("tjDecompress2(): Invalid argument");
if(flags&TJFLAG_FORCEMMX) putenv("JSIMD_FORCEMMX=1");
else if(flags&TJFLAG_FORCESSE) putenv("JSIMD_FORCESSE=1");
else if(flags&TJFLAG_FORCESSE2) putenv("JSIMD_FORCESSE2=1");
if(setjmp(this->jerr.setjmp_buffer))
{
/* If we get here, the JPEG code has signaled an error. */
retval=-1;
goto bailout;
}
this->jsrc.bytes_in_buffer=jpegSize;
this->jsrc.next_input_byte=jpegBuf;
jpeg_read_header(dinfo, TRUE);
if(setDecompDefaults(dinfo, pixelFormat)==-1)
{
retval=-1; goto bailout;
}
if(flags&TJFLAG_FASTUPSAMPLE) dinfo->do_fancy_upsampling=FALSE;
jpegwidth=dinfo->image_width; jpegheight=dinfo->image_height;
if(width==0) width=jpegwidth;
if(height==0) height=jpegheight;
for(i=0; i<NUMSF; i++)
{
scaledw=TJSCALED(jpegwidth, sf[i]);
scaledh=TJSCALED(jpegheight, sf[i]);
if(scaledw<=width && scaledh<=height)
break;
}
if(scaledw>width || scaledh>height)
_throw("tjDecompress2(): Could not scale down to desired image dimensions");
width=scaledw; height=scaledh;
dinfo->scale_num=sf[i].num;
dinfo->scale_denom=sf[i].denom;
jpeg_start_decompress(dinfo);
if(pitch==0) pitch=dinfo->output_width*tjPixelSize[pixelFormat];
#ifndef JCS_EXTENSIONS
if(pixelFormat!=TJPF_GRAY &&
(RGB_RED!=tjRedOffset[pixelFormat] ||
RGB_GREEN!=tjGreenOffset[pixelFormat] ||
RGB_BLUE!=tjBlueOffset[pixelFormat] ||
RGB_PIXELSIZE!=tjPixelSize[pixelFormat]))
{
rgbBuf=(unsigned char *)malloc(width*height*3);
if(!rgbBuf) _throw("tjDecompress2(): Memory allocation failure");
_pitch=pitch; pitch=width*3;
_dstBuf=dstBuf; dstBuf=rgbBuf;
}
#endif
if((row_pointer=(JSAMPROW *)malloc(sizeof(JSAMPROW)
*dinfo->output_height))==NULL)
_throw("tjDecompress2(): Memory allocation failure");
for(i=0; i<(int)dinfo->output_height; i++)
{
if(flags&TJFLAG_BOTTOMUP)
row_pointer[i]=&dstBuf[(dinfo->output_height-i-1)*pitch];
else row_pointer[i]=&dstBuf[i*pitch];
}
while(dinfo->output_scanline<dinfo->output_height)
{
jpeg_read_scanlines(dinfo, &row_pointer[dinfo->output_scanline],
dinfo->output_height-dinfo->output_scanline);
}
jpeg_finish_decompress(dinfo);
#ifndef JCS_EXTENSIONS
fromRGB(rgbBuf, _dstBuf, width, _pitch, height, pixelFormat);
#endif
bailout:
if(dinfo->global_state>DSTATE_START) jpeg_abort_decompress(dinfo);
#ifndef JCS_EXTENSIONS
if(rgbBuf) free(rgbBuf);
#endif
if(row_pointer) free(row_pointer);
return retval;
}
DLLEXPORT int DLLCALL tjDecompress(tjhandle handle, unsigned char *jpegBuf,
unsigned long jpegSize, unsigned char *dstBuf, int width, int pitch,
int height, int pixelSize, int flags)
{
return tjDecompress2(handle, jpegBuf, jpegSize, dstBuf, width, pitch,
height, getPixelFormat(pixelSize, flags), flags);
}

@ -0,0 +1,529 @@
/*
* Copyright (C)2009-2012 D. R. Commander. All Rights Reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions are met:
*
* - Redistributions of source code must retain the above copyright notice,
* this list of conditions and the following disclaimer.
* - Redistributions in binary form must reproduce the above copyright notice,
* this list of conditions and the following disclaimer in the documentation
* and/or other materials provided with the distribution.
* - Neither the name of the libjpeg-turbo Project nor the names of its
* contributors may be used to endorse or promote products derived from this
* software without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS",
* AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDERS OR CONTRIBUTORS BE
* LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
* CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
* SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
* INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
* CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
* ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
* POSSIBILITY OF SUCH DAMAGE.
*/
#ifndef __TURBOJPEG_H__
#define __TURBOJPEG_H__
#if defined(_WIN32) && defined(DLLDEFINE)
#define DLLEXPORT __declspec(dllexport)
#else
#define DLLEXPORT
#endif
#define DLLCALL
/**
* @addtogroup TurboJPEG Lite
* TurboJPEG API. This API provides an interface for generating and decoding
* JPEG images in memory.
*
* @{
*/
/**
* The number of chrominance subsampling options
*/
#define TJ_NUMSAMP 5
/**
* Chrominance subsampling options.
* When an image is converted from the RGB to the YCbCr colorspace as part of
* the JPEG compression process, some of the Cb and Cr (chrominance) components
* can be discarded or averaged together to produce a smaller image with little
* perceptible loss of image clarity (the human eye is more sensitive to small
* changes in brightness than small changes in color.) This is called
* "chrominance subsampling".
*/
enum TJSAMP
{
/**
* 4:4:4 chrominance subsampling (no chrominance subsampling). The JPEG or
* YUV image will contain one chrominance component for every pixel in the
* source image.
*/
TJSAMP_444=0,
/**
* 4:2:2 chrominance subsampling. The JPEG or YUV image will contain one
* chrominance component for every 2x1 block of pixels in the source image.
*/
TJSAMP_422,
/**
* 4:2:0 chrominance subsampling. The JPEG or YUV image will contain one
* chrominance component for every 2x2 block of pixels in the source image.
*/
TJSAMP_420,
/**
* Grayscale. The JPEG or YUV image will contain no chrominance components.
*/
TJSAMP_GRAY,
/**
* 4:4:0 chrominance subsampling. The JPEG or YUV image will contain one
* chrominance component for every 1x2 block of pixels in the source image.
*/
TJSAMP_440
};
/**
* MCU block width (in pixels) for a given level of chrominance subsampling.
* MCU block sizes:
* - 8x8 for no subsampling or grayscale
* - 16x8 for 4:2:2
* - 8x16 for 4:4:0
* - 16x16 for 4:2:0
*/
static const int tjMCUWidth[TJ_NUMSAMP] = {8, 16, 16, 8, 8};
/**
* MCU block height (in pixels) for a given level of chrominance subsampling.
* MCU block sizes:
* - 8x8 for no subsampling or grayscale
* - 16x8 for 4:2:2
* - 8x16 for 4:4:0
* - 16x16 for 4:2:0
*/
static const int tjMCUHeight[TJ_NUMSAMP] = {8, 8, 16, 8, 16};
/**
* The number of pixel formats
*/
#define TJ_NUMPF 11
/**
* Pixel formats
*/
enum TJPF
{
/**
* RGB pixel format. The red, green, and blue components in the image are
* stored in 3-byte pixels in the order R, G, B from lowest to highest byte
* address within each pixel.
*/
TJPF_RGB=0,
/**
* BGR pixel format. The red, green, and blue components in the image are
* stored in 3-byte pixels in the order B, G, R from lowest to highest byte
* address within each pixel.
*/
TJPF_BGR,
/**
* RGBX pixel format. The red, green, and blue components in the image are
* stored in 4-byte pixels in the order R, G, B from lowest to highest byte
* address within each pixel. The X component is ignored when compressing
* and undefined when decompressing.
*/
TJPF_RGBX,
/**
* BGRX pixel format. The red, green, and blue components in the image are
* stored in 4-byte pixels in the order B, G, R from lowest to highest byte
* address within each pixel. The X component is ignored when compressing
* and undefined when decompressing.
*/
TJPF_BGRX,
/**
* XBGR pixel format. The red, green, and blue components in the image are
* stored in 4-byte pixels in the order R, G, B from highest to lowest byte
* address within each pixel. The X component is ignored when compressing
* and undefined when decompressing.
*/
TJPF_XBGR,
/**
* XRGB pixel format. The red, green, and blue components in the image are
* stored in 4-byte pixels in the order B, G, R from highest to lowest byte
* address within each pixel. The X component is ignored when compressing
* and undefined when decompressing.
*/
TJPF_XRGB,
/**
* Grayscale pixel format. Each 1-byte pixel represents a luminance
* (brightness) level from 0 to 255.
*/
TJPF_GRAY,
/**
* RGBA pixel format. This is the same as @ref TJPF_RGBX, except that when
* decompressing, the X component is guaranteed to be 0xFF, which can be
* interpreted as an opaque alpha channel.
*/
TJPF_RGBA,
/**
* BGRA pixel format. This is the same as @ref TJPF_BGRX, except that when
* decompressing, the X component is guaranteed to be 0xFF, which can be
* interpreted as an opaque alpha channel.
*/
TJPF_BGRA,
/**
* ABGR pixel format. This is the same as @ref TJPF_XBGR, except that when
* decompressing, the X component is guaranteed to be 0xFF, which can be
* interpreted as an opaque alpha channel.
*/
TJPF_ABGR,
/**
* ARGB pixel format. This is the same as @ref TJPF_XRGB, except that when
* decompressing, the X component is guaranteed to be 0xFF, which can be
* interpreted as an opaque alpha channel.
*/
TJPF_ARGB
};
/**
* Red offset (in bytes) for a given pixel format. This specifies the number
* of bytes that the red component is offset from the start of the pixel. For
* instance, if a pixel of format TJ_BGRX is stored in <tt>char pixel[]</tt>,
* then the red component will be <tt>pixel[tjRedOffset[TJ_BGRX]]</tt>.
*/
static const int tjRedOffset[TJ_NUMPF] = {0, 2, 0, 2, 3, 1, 0, 0, 2, 3, 1};
/**
* Green offset (in bytes) for a given pixel format. This specifies the number
* of bytes that the green component is offset from the start of the pixel.
* For instance, if a pixel of format TJ_BGRX is stored in
* <tt>char pixel[]</tt>, then the green component will be
* <tt>pixel[tjGreenOffset[TJ_BGRX]]</tt>.
*/
static const int tjGreenOffset[TJ_NUMPF] = {1, 1, 1, 1, 2, 2, 0, 1, 1, 2, 2};
/**
* Blue offset (in bytes) for a given pixel format. This specifies the number
* of bytes that the Blue component is offset from the start of the pixel. For
* instance, if a pixel of format TJ_BGRX is stored in <tt>char pixel[]</tt>,
* then the blue component will be <tt>pixel[tjBlueOffset[TJ_BGRX]]</tt>.
*/
static const int tjBlueOffset[TJ_NUMPF] = {2, 0, 2, 0, 1, 3, 0, 2, 0, 1, 3};
/**
* Pixel size (in bytes) for a given pixel format.
*/
static const int tjPixelSize[TJ_NUMPF] = {3, 3, 4, 4, 4, 4, 1, 4, 4, 4, 4};
/**
* The uncompressed source/destination image is stored in bottom-up (Windows,
* OpenGL) order, not top-down (X11) order.
*/
#define TJFLAG_BOTTOMUP 2
/**
* Turn off CPU auto-detection and force TurboJPEG to use MMX code (IPP and
* 32-bit libjpeg-turbo versions only.)
*/
#define TJFLAG_FORCEMMX 8
/**
* Turn off CPU auto-detection and force TurboJPEG to use SSE code (32-bit IPP
* and 32-bit libjpeg-turbo versions only)
*/
#define TJFLAG_FORCESSE 16
/**
* Turn off CPU auto-detection and force TurboJPEG to use SSE2 code (32-bit IPP
* and 32-bit libjpeg-turbo versions only)
*/
#define TJFLAG_FORCESSE2 32
/**
* Turn off CPU auto-detection and force TurboJPEG to use SSE3 code (64-bit IPP
* version only)
*/
#define TJFLAG_FORCESSE3 128
/**
* Use fast, inaccurate chrominance upsampling routines in the JPEG
* decompressor (libjpeg and libjpeg-turbo versions only)
*/
#define TJFLAG_FASTUPSAMPLE 256
/**
* Scaling factor
*/
typedef struct
{
/**
* Numerator
*/
int num;
/**
* Denominator
*/
int denom;
} tjscalingfactor;
/**
* TurboJPEG instance handle
*/
typedef void* tjhandle;
/**
* Pad the given width to the nearest 32-bit boundary
*/
#define TJPAD(width) (((width)+3)&(~3))
/**
* Compute the scaled value of <tt>dimension</tt> using the given scaling
* factor. This macro performs the integer equivalent of <tt>ceil(dimension *
* scalingFactor)</tt>.
*/
#define TJSCALED(dimension, scalingFactor) ((dimension * scalingFactor.num \
+ scalingFactor.denom - 1) / scalingFactor.denom)
#ifdef __cplusplus
extern "C" {
#endif
/**
* Create a TurboJPEG compressor instance.
*
* @return a handle to the newly-created instance, or NULL if an error
* occurred (see #tjGetErrorStr().)
*/
DLLEXPORT tjhandle DLLCALL tjInitCompress(void);
/**
* Compress an RGB or grayscale image into a JPEG image.
*
* @param handle a handle to a TurboJPEG compressor or transformer instance
* @param srcBuf pointer to an image buffer containing RGB or grayscale pixels
* to be compressed
* @param width width (in pixels) of the source image
* @param pitch bytes per line of the source image. Normally, this should be
* <tt>width * #tjPixelSize[pixelFormat]</tt> if the image is unpadded,
* or <tt>#TJPAD(width * #tjPixelSize[pixelFormat])</tt> if each line of
* the image is padded to the nearest 32-bit boundary, as is the case
* for Windows bitmaps. You can also be clever and use this parameter
* to skip lines, etc. Setting this parameter to 0 is the equivalent of
* setting it to <tt>width * #tjPixelSize[pixelFormat]</tt>.
* @param height height (in pixels) of the source image
* @param pixelFormat pixel format of the source image (see @ref TJPF
* "Pixel formats".)
* @param jpegBuf address of a pointer to an image buffer that will receive the
* JPEG image. TurboJPEG has the ability to reallocate the JPEG buffer
* to accommodate the size of the JPEG image. Thus, you can choose to:
* -# pre-allocate the JPEG buffer with an arbitrary size using
* #tjAlloc() and let TurboJPEG grow the buffer as needed,
* -# set <tt>*jpegBuf</tt> to NULL to tell TurboJPEG to allocate the
* buffer for you, or
* -# pre-allocate the buffer to a "worst case" size determined by
* calling #tjBufSize(). This should ensure that the buffer never has
* to be re-allocated (setting #TJFLAG_NOREALLOC guarantees this.)
* .
* If you choose option 1, <tt>*jpegSize</tt> should be set to the
* size of your pre-allocated buffer. In any case, unless you have
* set #TJFLAG_NOREALLOC, you should always check <tt>*jpegBuf</tt> upon
* return from this function, as it may have changed.
* @param jpegSize pointer to an unsigned long variable that holds the size of
* the JPEG image buffer. If <tt>*jpegBuf</tt> points to a
* pre-allocated buffer, then <tt>*jpegSize</tt> should be set to the
* size of the buffer. Upon return, <tt>*jpegSize</tt> will contain the
* size of the JPEG image (in bytes.)
* @param jpegSubsamp the level of chrominance subsampling to be used when
* generating the JPEG image (see @ref TJSAMP
* "Chrominance subsampling options".)
* @param jpegQual the image quality of the generated JPEG image (1 = worst,
100 = best)
* @param flags the bitwise OR of one or more of the @ref TJFLAG_BOTTOMUP
* "flags".
*
* @return 0 if successful, or -1 if an error occurred (see #tjGetErrorStr().)
*/
DLLEXPORT int DLLCALL tjCompress2(tjhandle handle, unsigned char *srcBuf,
int width, int pitch, int height, int pixelFormat, unsigned char **jpegBuf,
unsigned long *jpegSize, int jpegSubsamp, int jpegQual, int flags);
/**
* The maximum size of the buffer (in bytes) required to hold a JPEG image with
* the given parameters. The number of bytes returned by this function is
* larger than the size of the uncompressed source image. The reason for this
* is that the JPEG format uses 16-bit coefficients, and it is thus possible
* for a very high-quality JPEG image with very high frequency content to
* expand rather than compress when converted to the JPEG format. Such images
* represent a very rare corner case, but since there is no way to predict the
* size of a JPEG image prior to compression, the corner case has to be
* handled.
*
* @param width width of the image (in pixels)
* @param height height of the image (in pixels)
* @param jpegSubsamp the level of chrominance subsampling to be used when
* generating the JPEG image (see @ref TJSAMP
* "Chrominance subsampling options".)
*
* @return the maximum size of the buffer (in bytes) required to hold the
* image, or -1 if the arguments are out of bounds.
*/
DLLEXPORT unsigned long DLLCALL tjBufSize(int width, int height,
int jpegSubsamp);
/**
* Create a TurboJPEG decompressor instance.
*
* @return a handle to the newly-created instance, or NULL if an error
* occurred (see #tjGetErrorStr().)
*/
DLLEXPORT tjhandle DLLCALL tjInitDecompress(void);
/**
* Retrieve information about a JPEG image without decompressing it.
*
* @param handle a handle to a TurboJPEG decompressor or transformer instance
* @param jpegBuf pointer to a buffer containing a JPEG image
* @param jpegSize size of the JPEG image (in bytes)
* @param width pointer to an integer variable that will receive the width (in
* pixels) of the JPEG image
* @param height pointer to an integer variable that will receive the height
* (in pixels) of the JPEG image
* @param jpegSubsamp pointer to an integer variable that will receive the
* level of chrominance subsampling used when compressing the JPEG image
* (see @ref TJSAMP "Chrominance subsampling options".)
*
* @return 0 if successful, or -1 if an error occurred (see #tjGetErrorStr().)
*/
DLLEXPORT int DLLCALL tjDecompressHeader2(tjhandle handle,
unsigned char *jpegBuf, unsigned long jpegSize, int *width, int *height,
int *jpegSubsamp);
/**
* Returns a list of fractional scaling factors that the JPEG decompressor in
* this implementation of TurboJPEG supports.
*
* @param numscalingfactors pointer to an integer variable that will receive
* the number of elements in the list
*
* @return a pointer to a list of fractional scaling factors, or NULL if an
* error is encountered (see #tjGetErrorStr().)
*/
DLLEXPORT tjscalingfactor* DLLCALL tjGetScalingFactors(int *numscalingfactors);
/**
* Decompress a JPEG image to an RGB or grayscale image.
*
* @param handle a handle to a TurboJPEG decompressor or transformer instance
* @param jpegBuf pointer to a buffer containing the JPEG image to decompress
* @param jpegSize size of the JPEG image (in bytes)
* @param dstBuf pointer to an image buffer that will receive the decompressed
* image. This buffer should normally be <tt>pitch * scaledHeight</tt>
* bytes in size, where <tt>scaledHeight</tt> can be determined by
* calling #TJSCALED() with the JPEG image height and one of the scaling
* factors returned by #tjGetScalingFactors(). The dstBuf pointer may
* also be used to decompress into a specific region of a larger buffer.
* @param width desired width (in pixels) of the destination image. If this is
* smaller than the width of the JPEG image being decompressed, then
* TurboJPEG will use scaling in the JPEG decompressor to generate the
* largest possible image that will fit within the desired width. If
* width is set to 0, then only the height will be considered when
* determining the scaled image size.
* @param pitch bytes per line of the destination image. Normally, this is
* <tt>scaledWidth * #tjPixelSize[pixelFormat]</tt> if the decompressed
* image is unpadded, else <tt>#TJPAD(scaledWidth *
* #tjPixelSize[pixelFormat])</tt> if each line of the decompressed
* image is padded to the nearest 32-bit boundary, as is the case for
* Windows bitmaps. (NOTE: <tt>scaledWidth</tt> can be determined by
* calling #TJSCALED() with the JPEG image width and one of the scaling
* factors returned by #tjGetScalingFactors().) You can also be clever
* and use the pitch parameter to skip lines, etc. Setting this
* parameter to 0 is the equivalent of setting it to <tt>scaledWidth
* * #tjPixelSize[pixelFormat]</tt>.
* @param height desired height (in pixels) of the destination image. If this
* is smaller than the height of the JPEG image being decompressed, then
* TurboJPEG will use scaling in the JPEG decompressor to generate the
* largest possible image that will fit within the desired height. If
* height is set to 0, then only the width will be considered when
* determining the scaled image size.
* @param pixelFormat pixel format of the destination image (see @ref
* TJPF "Pixel formats".)
* @param flags the bitwise OR of one or more of the @ref TJFLAG_BOTTOMUP
* "flags".
*
* @return 0 if successful, or -1 if an error occurred (see #tjGetErrorStr().)
*/
DLLEXPORT int DLLCALL tjDecompress2(tjhandle handle,
unsigned char *jpegBuf, unsigned long jpegSize, unsigned char *dstBuf,
int width, int pitch, int height, int pixelFormat, int flags);
/**
* Destroy a TurboJPEG compressor, decompressor, or transformer instance.
*
* @param handle a handle to a TurboJPEG compressor, decompressor or
* transformer instance
*
* @return 0 if successful, or -1 if an error occurred (see #tjGetErrorStr().)
*/
DLLEXPORT int DLLCALL tjDestroy(tjhandle handle);
/**
* Returns a descriptive error message explaining why the last command failed.
*
* @return a descriptive error message explaining why the last command failed.
*/
DLLEXPORT char* DLLCALL tjGetErrorStr(void);
/* Backward compatibility functions and macros (nothing to see here) */
#define NUMSUBOPT TJ_NUMSAMP
#define TJ_444 TJSAMP_444
#define TJ_422 TJSAMP_422
#define TJ_420 TJSAMP_420
#define TJ_411 TJSAMP_420
#define TJ_GRAYSCALE TJSAMP_GRAY
#define TJ_BGR 1
#define TJ_BOTTOMUP TJFLAG_BOTTOMUP
#define TJ_FORCEMMX TJFLAG_FORCEMMX
#define TJ_FORCESSE TJFLAG_FORCESSE
#define TJ_FORCESSE2 TJFLAG_FORCESSE2
#define TJ_ALPHAFIRST 64
#define TJ_FORCESSE3 TJFLAG_FORCESSE3
#define TJ_FASTUPSAMPLE TJFLAG_FASTUPSAMPLE
DLLEXPORT unsigned long DLLCALL TJBUFSIZE(int width, int height);
DLLEXPORT int DLLCALL tjCompress(tjhandle handle, unsigned char *srcBuf,